This invention relates to a controlled deflection roll. More particularly, this invention relates to a self-loading type of controlled deflection roll wherein the roll is capable of being moved into and out of nipping engagement with another roll without having to move the support shafts of either roll toward the other roll. Such rolls are very useful in the papermaking industry where it is desirable, and necessary, to create a gap of up to several inches between rolls which otherwise are engaged in a nip-line of contact during normal operation.
The creation of such a gap is important during the papermaking process in order to change the felt in a press section of a papermaking machine as well as to remove wads of paper which might accumulate during a sheet break or other interruption of the travel of the paper web. Such interruptions are also often encountered during the operation of calendar stacks, and this type of roll is useful there as well.
Other types of self-loading controlled deflection rolls are known. Examples are shown and described in U.S. Pat. Nos. 3,885,283; 4,249,290 and 4,213,232. The purpose of all self-loading types of controlled deflection rolls is the same, and that is to move the roll shell radially relative to the axis of the roll without use of external support arms. This greatly simplifies mounting the controlled deflection roll in a papermaking machine as well as reduces the space required.
Prior self-loading controlled deflection rolls operate by utilizing a stationary center shaft, or support beam, over which the roll shell is translationally movable and supported on hydraulically actuated support elements, or shoes. The roll shell is rotatably supported on a ring which also moves translationally relative to the support beam. The ring is guided in its movement by parallel surfaces which slide over corresponding surfaces on the shaft.